JP2005313361A - Medical image recording apparatus and medical image recording method - Google Patents

Abstract

An object of the present invention is to easily and highly accurately correct image unevenness.
A solid image of a plurality of regions corrected by a correction amount based on a plurality of different shading correction parameters and an identification code representing the shading correction parameter are recorded as a test pattern in an image output unit 10 as a medical image recording unit. A shading correction parameter that is recorded on the medium and has the smallest density difference in the main scanning direction of the solid image recorded is set and input via the correction parameter input unit 4, and based on the input shading correction parameter. Then, a shading correction table for correcting shading is created, the medical image is corrected using the shading correction table, and the image output unit 10 records an image on a recording medium.
[Selection] Figure 1

Description

  The present invention relates to a medical image recording apparatus and a medical image recording method for recording a medical image on a recording medium.

In recent years, a method for obtaining medical radiographic image information without using a radiographic film made of a silver salt photosensitive material has been devised. For example, using an imaging plate mainly composed of photostimulable phosphors, radiation images are obtained by temporarily accumulating radiation images, extracting them as stimulating light using excitation light, and photoelectrically converting this light. An apparatus (Computed Radiography, hereinafter abbreviated as CR) has become widespread.
Recently, an apparatus (Flat Panel Detector, hereinafter abbreviated as FPD) that reads radiation image information by combining a radiation phosphor or radiation photoconductor with a two-dimensional semiconductor detector such as a TFT switching element has been proposed.

  In diagnosing these medical images, a method of recording image information on at least one of a transmissive recording medium and a reflective recording medium and observing it in the form of a hard copy is often used. As a medical image recording apparatus for recording medical image information on a recording medium, a method of recording an image by laser exposure on a transmission recording medium using a silver salt recording material is often used. According to this method, a monochrome multi-gradation image can be drawn with excellent gradation, and high diagnostic ability can be obtained by recording on a transmission medium and observing with transmitted light.

  Various types of medical image recording apparatuses have been developed, and in addition to using conventional silver salt recording materials that require wet processing, thermal recording apparatuses using thermal heads or heat mode lasers, photosensitive thermal development, and the like. An apparatus for recording a photothermographic image by using a recording material or a photothermographic material is also known.

  Also, a method for inspecting defects in image display and image recording has been considered. For example, in a display system, a digital test image is created and displayed from a visual configuration test pattern, and contrast calibration is inspected by observing the digital test image (see, for example, Patent Document 1).

  Further, in the thermal development apparatus, a test pattern is recorded on a storage medium, the average density of the test pattern is measured with a densitometer, and the reduction in sharpness due to the deviation of the optical system is corrected based on the measurement result. Calibration is considered (see, for example, Patent Document 2).

In addition, in an inkjet printer, a plurality of test patterns are recorded on a recording medium, and an appropriate γ correction table is selected according to the test pattern that is selected as the most smooth by the observer, and the γ correction table is used to select a floor pattern. By adjusting the tone, variations in the heaters and ejection openings during manufacture of the ink jet printer, the amount of recording medium transported, the change in ink density due to the difference in recording time, and the image unevenness caused by the change in ink density on the recording medium The structure which correct | amends generation | occurrence | production of this is considered (for example, refer patent document 3).
JP-A-11-327501 Japanese Patent Laid-Open No. 2003-162008 JP 2000-307864 A

  Particularly in a medical image recording apparatus, it is preferable to record an image with extremely high resolution. Further, in a laser type image recording apparatus, it is necessary to correct image unevenness that occurs in the main scanning direction and periodic unevenness (banding) that occurs in the sub-scanning direction due to a positional deviation of the optical system. . This is because these image unevenness may deteriorate image quality and cause misdiagnosis.

  FIG. 21 shows an example of uneven exposure amount with respect to the X axis (main scanning direction). In an image recording apparatus, a laser for exposing a recording medium is reflected on each surface of a rotating polygon mirror and exposed to the recording medium via an fθ lens and a cylindrical lens. Each surface of the rotary polygon mirror deserves one scanning line on the recording medium. However, depending on the condensing position (recording medium width position) of the fθ lens, as shown in FIG. 21, unevenness of the exposure amount occurs on one scanning line, resulting in image unevenness in the main scanning direction.

  FIG. 22 shows an example of uneven exposure amount with respect to the Y axis (sub-scanning direction). In an image recording apparatus, the total number of rotating polygon mirrors is set to one period due to variations (individual differences) in the light reflectance of each surface of the rotating polygon mirror for reflecting the laser and periodic variations due to surface tilt of each surface. The streak unevenness in the main scanning direction occurs with respect to the sub-scanning direction, and the unevenness in the image in the sub-scanning direction occurs. FIG. 22 shows a case where the number of entire surfaces of the rotary polygon mirror is 6 and streak unevenness occurs in two rasters A and B in all rasters in recording a solid image.

  However, in the configuration described in Patent Document 1, the contrast calibration result is inspected. For this reason, for example, the observer has to perform contrast adjustment work based on the inspection result, and there is a possibility that the work burden may not be reduced.

  Further, in the configuration described in Patent Document 2, it is a configuration that detects image unevenness caused by a positional shift of the optical system in the laser type image recording apparatus, but is a configuration that inspects the shift of the optical system. The observer had to inform the supplier of the fact that the optical system was displaced, and the image could not be corrected and recorded. In addition, in recent medical image recording, the recording pitch for sub-scanning is extremely small and density measurement is extremely difficult, and a special optical densitometer such as a microdensitometer as in the configuration described in Patent Document 2 is used. When measuring with the use of, there was a problem that the measurement burden was large.

  In the configuration described in Patent Document 3, a correction γ table is selected based on the selected test pattern and image correction is performed using the γ table. However, image unevenness is still simple and high. There is a request to correct the accuracy.

  An object of the present invention is to make it possible to easily and highly accurately correct image unevenness.

In order to solve the above problem, the invention according to claim 1 is a medical image recording apparatus for recording a medical image on a recording medium.
Image recording means for recording the image by exposing and scanning the recording medium;
Test pattern recording control for causing the image recording unit to record an image on the recording medium as a test pattern of a solid image of a plurality of regions corrected by a correction amount based on a plurality of different shading correction parameters and an identification code representing the shading correction parameter Means,
Select a shading correction parameter that is determined based on the result of measuring the density in the main scanning direction of the solid image recorded by the test pattern recording control unit and that minimizes the difference in the density of the solid image in the main scanning direction. Input means for inputting;
A shading correction table creating means for creating a shading correction table for correcting shading based on the shading correction parameter input by the input means;
Medical image recording control means for applying a shading correction to a medical image using the shading correction table created by the shading correction table creating means and causing the image recording means to record an image on a recording medium;
It is characterized by providing.

The invention according to claim 7 is a medical image recording method for recording a medical image on a recording medium.
A step of recording an image on the recording medium as a test pattern with a solid image of a plurality of areas of the recording medium corrected by a correction amount based on a plurality of different shading correction parameters, and an identification code representing the shading correction parameter;
A step of selectively inputting a shading correction parameter that is determined based on the result of measuring the density in the main scanning direction of the solid image recorded in the image and that minimizes the difference in density of the solid image in the main scanning direction;
Creating a shading correction table for correcting shading based on the input shading correction parameters;
Performing a shading correction on a medical image using the created shading correction table and recording an image on a recording medium;
It is characterized by including.

  According to the first or seventh aspect of the invention, the user can easily select and input the optimum shading correction parameter by visually observing the test pattern, and automatically create a shading correction table based on the optimum shading correction parameter. Therefore, the medical image can be shading corrected with high accuracy using an optimum shading correction table created by a simple operation input by the user, and recorded on a recording medium.

The invention according to claim 2 is the medical image recording apparatus according to claim 1,
The test pattern recording control unit causes the image recording unit to record a mark on the recording medium to indicate a region where the density is to be measured.

The invention according to claim 8 is the medical image recording method according to claim 7,
In the step of recording the test pattern, a mark for indicating a region where the density is to be measured is recorded on the recording medium.

  According to the second or eighth aspect of the invention, since the mark indicating the area whose density is to be measured is recorded on the recording medium, the user can easily select the correction parameter of the optimum area based on the mark, and the optimum By selecting and inputting correct correction parameters, the correction accuracy of shading correction can be further improved.

The invention according to claim 3 is the medical image recording apparatus according to claim 1 or 2,
The number of solid images in the main scanning direction is an odd number.

The invention according to claim 9 is the medical image recording method according to claim 7 or 8,
The number of solid images in the main scanning direction is an odd number.

  According to the invention described in claim 3 or 9, since the test pattern includes an odd number of solid images in the main scanning direction, the user can easily and optimally correct the correction with the central area having the smallest correction amount as a reference. Parameters can be selected.

The invention according to claim 4 is the medical image recording apparatus according to any one of claims 1 to 3,
The shading correction table creating means creates a temporary shading correction table corresponding to a subaddress indicating a position for each of a plurality of pixels in the main scanning direction based on the shading correction parameter, and sets a subaddress of the temporary shading correction table. A shading correction table is created by interpolation.

The invention according to claim 10 is the medical image recording method according to any one of claims 7 to 9,
In the step of creating the shading correction table, a temporary shading correction table corresponding to a subaddress indicating the position of each of a plurality of pixels in the main scanning direction is created based on the shading correction parameter, and the subaddress of the temporary shading correction table A shading correction table is created by interpolating.

  According to the invention described in claim 4 or 10, first, a shading correction table corresponding to a sub-address for each predetermined number of pixels in the main scanning direction is created, and the shading correction table corresponding to the sub-address is interpolated to generate the shading correction table. Since it is created, the shading correction table can be created at high speed using the periodicity of the subaddress.

The invention according to claim 5 is a medical image recording apparatus for recording a medical image on a recording medium.
Different from the image recording means for exposing and scanning the recording medium to record an image, a solid image of a plurality of regions corrected by a correction amount based on a plurality of pitch unevenness correction parameters, and an identification code representing the pitch unevenness correction parameter as a test pattern Test pattern recording control means for causing the image recording means to record an image on the recording medium;
Input means for selecting and inputting a pitch unevenness correction parameter having the smallest pitch unevenness determined based on the result of visual evaluation of the solid image recorded by the test pattern recording control means;
Pitch unevenness correction table creating means for creating a pitch unevenness correction table for correcting pitch unevenness based on the pitch unevenness correction parameter input by the input means;
Medical image recording control means for performing pitch unevenness correction on a medical image using the pitch unevenness correction table created by the pitch unevenness correction table creating means, and causing the image recording means to record an image on a recording medium;
It is characterized by providing.

The invention according to claim 11 is a medical image recording method for recording a medical image on a recording medium.
A step of recording an image on the recording medium as a test pattern with a solid image of a plurality of regions corrected by a correction amount based on a plurality of different pitch unevenness correction parameters, and an identification code representing the pitch unevenness correction parameter;
A step of selectively inputting a pitch unevenness correction parameter having the smallest pitch unevenness determined based on a result of visual evaluation of the solid image recorded as described above;
Creating a pitch unevenness correction table for correcting pitch unevenness based on the input pitch unevenness correction parameters;
A step of performing pitch unevenness correction on a medical image using the created pitch unevenness correction table and recording an image on a recording medium;
It is characterized by including.

  According to the invention described in claim 5 or 11, the user can easily select and input the optimum pitch unevenness correction parameter by visually observing the test pattern, and the optimum pitch unevenness correction table is automatically generated based on the optimum pitch unevenness correction parameter. Therefore, the medical image can be recorded on the recording medium with high-precision pitch unevenness correction using the optimum pitch unevenness correction table by a simple operation input by the user.

The invention according to claim 6 is the medical image recording apparatus according to claim 5,
The test pattern recording control unit causes the image recording unit to record a mark for indicating the region to be visually evaluated on the recording medium.

The invention according to claim 12 is the medical image recording method according to claim 11,
In the test pattern recording step, a mark for indicating the region to be visually evaluated is recorded on the recording medium.

  According to the invention described in claim 6 or 12, since the mark indicating the area to be visually evaluated is recorded on the recording medium, the user can easily select the correction parameter of the optimum area based on the mark, and the pitch unevenness correction. The correction accuracy can be further improved.

  According to the first or seventh aspect of the invention, the user can easily select and input the optimum shading correction parameter by visually observing the test pattern, and automatically create a shading correction table based on the optimum shading correction parameter. Therefore, the medical image can be shading corrected with high accuracy using an optimum shading correction table created by a simple operation input by the user, and recorded on a recording medium.

  According to the second or eighth aspect of the invention, since the mark indicating the area whose density is to be measured is recorded on the recording medium, the user can easily select the correction parameter of the optimum area based on the mark, and the optimum By selecting and inputting correct correction parameters, the correction accuracy of shading correction can be further improved.

  According to the invention described in claim 3 or 9, since the test pattern includes an odd number of solid images in the main scanning direction, the user can easily and optimally correct the correction with the central area having the smallest correction amount as a reference. Parameters can be selected.

  According to the invention described in claim 4 or 10, first, a shading correction table corresponding to a sub-address for each predetermined number of pixels in the main scanning direction is created, and the shading correction table corresponding to the sub-address is interpolated to generate the shading correction table. Since it is created, the shading correction table can be created at high speed using the periodicity of the subaddress.

  According to the invention described in claim 5 or 11, the user can easily select and input the optimum pitch unevenness correction parameter by visually observing the test pattern, and the optimum pitch unevenness correction table is automatically generated based on the optimum pitch unevenness correction parameter. Therefore, the medical image can be recorded on the recording medium with high-precision pitch unevenness correction using the optimum pitch unevenness correction table by a simple operation input by the user.

  According to the invention described in claim 6 or 12, since the mark indicating the area to be visually evaluated is recorded on the recording medium, the user can easily select the correction parameter of the optimum area based on the mark, and the pitch unevenness correction. The correction accuracy can be further improved.

  Hereinafter, first and second embodiments of the present invention and modifications thereof will be described in detail with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples.

(First embodiment)
A first embodiment according to the present invention will be described with reference to FIGS. In the present embodiment, shading correction is performed to correct image unevenness in the main scanning direction of the recording medium. First, the apparatus configuration of the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 shows an internal configuration of the medical image recording apparatus 1 of the present embodiment. FIG. 2 shows an internal configuration of the exposure unit 13.

  As shown in FIG. 1, a medical image recording apparatus 1 according to the present embodiment includes an I / F (interface) 2, a control unit 3, a correction parameter input unit 4, a correction table calculation unit 5, and a data storage unit. 6, a film transport unit 7, and an image output unit 10. The image output unit 10 includes an image processing unit 11, a D / A conversion unit 12, an exposure unit 13, and a heat development unit 14.

  The I / F 2 connects the medical image recording apparatus 1 and the modality 20 for communication. The modality 20 is an apparatus that captures or reads a medical image of an affected area of a patient and outputs digital image data. For example, a CR apparatus, a CT (Computerized Tomography) apparatus, an MRI (Magnetic Resonance Imaging). Video) device. Digital image data output from the modality 20 is input to the medical image recording apparatus 1 via the I / F 2. Further, the I / F 2 inputs an image output instruction to the control unit 3 using the input of image data as a trigger.

  The control unit 3 includes a CPU, a RAM, and a ROM, and controls each unit in the medical image recording apparatus 1. The control unit 3 inputs an image output instruction to the image output unit 10 based on the image output instruction from the I / F 2. The correction parameter input unit 4 includes various operation keys and receives a correction parameter selection input from the user and outputs it to the control unit 3. The correction table calculation unit 5 calculates a correction table according to an instruction from the control unit 3 and outputs the correction table to the control unit 3. The data storage unit 6 stores the correction table calculated by the correction table calculation unit 5 and outputs the correction table to the image processing unit 11 according to an instruction from the control unit 3. The film transport unit 7 includes a transport roller 71 and the like, and transports a film F as a medical image recording medium according to an instruction from the control unit 3.

  The image processing unit 11 performs various processes on the image data input to the medical image recording apparatus 1 via the I / F 2 according to instructions from the control unit 3, and uses the correction table read from the data storage unit 6. Correct the image data. The D / A conversion unit 12 converts the digital image data after image processing input from the image processing unit 11 into an analog signal according to an instruction from the control unit 3. The exposure unit 13 uses the analog image data after image processing input from the D / A conversion unit 12 according to an instruction from the control unit 3 to laser the film F conveyed by the conveyance roller 71 of the film conveyance unit 7. A latent image of a medical image is formed by irradiation of. The heat developing unit 14 includes a rotatable roller that can be heated in accordance with an instruction from the control unit 3, and heats the film F by bringing the film F exposed by the exposure unit 13 into close contact with the outer periphery of the heated rotating roller. Thus, the latent image on the film F is visualized to develop the medical image.

  Here, the exposure unit 13 will be described in detail with reference to FIG. As shown in FIG. 2, the exposure unit 13 includes a modulation unit 131, a laser light source unit 132, a condenser lens 133, a cylindrical lens 134, a rotary polygon mirror 135, an fθ lens 136, and a mirror 137. It is prepared for.

  The modulation unit 131 modulates the intensity of the laser light L based on the analog signal of the image data input from the D / A conversion unit 12 and generates a light emission intensity control signal. The laser light source unit 132 emits the laser light L based on the light emission intensity control signal input from the modulation unit 131. The condenser lens 133 collimates the laser light L by passing the laser light L. The cylindrical lens 134 converges the laser light L in one direction by passing the laser light L. That is, the cylindrical lens 134 images the laser light L on each surface of the rotary polygon mirror 135 in the main scanning direction.

  The rotary polygon mirror 135 has six mirror surfaces, rotates in the rotation direction A about the axis, and reflects the laser light L on each surface. In this embodiment, the number of mirror surfaces is six, but other numbers may be used. Each surface of the rotary polygon mirror 135 can be regarded as a virtual light source from which the reflected laser light L is emitted. The fθ lens 136 corrects the scanning speed of the laser light L reflected on each surface of the rotary polygon mirror 135 by the passage of the laser light L. That is, the distance from each surface of the rotary polygon mirror 135 as a virtual light source to the recording surface of the film F varies depending on the orientation of the rotary polygon mirror 135, and the influence on the main scanning speed due to the change in the distance is corrected. The fθ lens 136 also has a function of forming an image of the laser light L reflected by each surface of the rotary polygon mirror 135 on the mirror 137 in the main scanning direction. The mirror 137 reflects the laser light L that has passed through the fθ lens 136 and irradiates the recording surface of the film F.

  One surface of the rotary polygon mirror 135 corresponds to one scan. Depending on the condensing position of the laser light L emitted from the fθ lens 136, a difference in the amount of light applied to the film F occurs in the main scanning direction (X-axis direction), and image unevenness occurs in the main scanning direction. That is, as shown in FIG. 21, since the exposure amount at the central portion of the film F in the main scanning direction is large, the recorded image becomes dark, and the exposure amount decreases toward the end portion, so that the recorded image becomes thin.

  FIG. 3 shows an example of a shading correction table used for shading correction. As in the shading correction table shown in FIG. 3, the correction amount of the exposure amount (density) of the central portion of the film F is reduced in the X-axis direction, and correction that increases toward the end portion is required.

  Next, the operation of the medical image recording apparatus 1 will be described with reference to FIGS. A first test pattern recording process for recording a test pattern for selecting an optimum correction parameter for shading correction on the film F will be described with reference to FIG. FIG. 4 shows the first test pattern recording process. For example, when a test pattern recording instruction is input via the correction parameter input unit 4, the first test pattern recording program stored in the ROM in the control unit 3 is read and triggered in the control unit 3. The first test pattern recording process is executed in cooperation with the CPU in the control unit 3 and the first test pattern recording program.

  First, a test pattern for shading correction is created based on the graph of the relationship between the correction parameter and the exposure amount correction amount stored in the data storage unit 6 (step S11). Here, the creation of the test pattern in step S11 will be described in detail with reference to FIGS. FIG. 5 shows an example of the relationship of the correction amount to the correction parameter. FIG. 6 shows an output example of a test pattern for shading correction.

  In shading correction for image unevenness in the main scanning direction, a test pattern composed of divided regions having a plurality of correction parameters is created. The observer observes the divided areas of the correction parameters in the test pattern, and the observer selects the optimum correction parameters of the divided areas without image unevenness. This is because an optimal shading correction table is generated using the selected optimal correction parameter.

  For example, the correction parameter when the correction amount is 0 is set as the reference (0), as shown in FIG. The correction parameter is an exposure amount correction amount (%) pattern corresponding to 15 points from -7 to 0 to +7. According to the relationship of FIG. 5, the correction amount increases as the correction parameter increases. When the correction parameter is 0, the correction amount is 0. When the correction parameter is a positive value, the correction amount is also a positive value. When the parameter is a negative value, the correction amount is also a negative value. That is, as the correction parameter is a positive value and increases, the image data is corrected so that the exposure amount increases, and the output density of the image also increases. When the correction parameter is 0, no correction is made and the output density of the image does not change. Further, as the correction parameter is a negative value and becomes smaller, the image data is corrected so that the exposure amount is reduced, and the output density of the image is also lowered.

  As shown in FIG. 6, the test pattern 30 has a recording surface of the film F that is divided into three equal parts in the main scanning direction and is divided into a central area, a right area, and a left area, and the number of correction parameters in the sub-scanning direction. Is divided equally. In this way, 3 × 15 divided regions 31 are formed. The correction parameter 0 is associated with the divided area 31 of the central area. Then, the left and right divided areas 31 are sequentially associated with the correction parameter from the highest value to the lowest value from top to bottom.

  In the divided area 31, a solid image having a density of one color has a density corrected by a correction amount corresponding to each correction parameter, and becomes a substantially uniform density image. A correction parameter (value) 32 is entered in the divided area 31. Further, the divided area 31 is divided by a frame 33 as a mark indicating the density observation area. With reference to the test pattern 30 stored on the film F, the observer can visually determine the divided area 31 having the smoothest density with no image unevenness in the main scanning direction.

  Then, the test pattern created in step S11 is input to the image processing unit 11, and an image is recorded on the film F by the image output unit 10 (step S12), and the first test pattern recording process is terminated.

  Next, a shading correction table storage process for creating and storing a shading correction table used for shading correction will be described with reference to FIG. FIG. 7 shows the shading correction table storage process. For example, when a shading correction table creation instruction is input via the correction parameter input unit 4, the shading correction table storage program stored in the ROM in the control unit 3 is read and the RAM in the control unit 3 is read. The shading correction table storage process is executed in cooperation with the CPU in the control unit 3 and the shading correction table storage program.

  First, the address in the main scanning direction and the sub address are calculated by the correction table calculation unit 5 (step S21). Here, with reference to FIG. 8, the addresses and subaddresses of the pixels to be recorded on the film F will be described. FIG. 8 shows the sub-address of the pixel recorded on the film F, (a) shows the pixel for each sub-address recorded on the film F, and (b) shows the correspondence between the pixel address and the sub-address.

  A plurality of pixels are recorded on one scanning line in the main scanning (X-axis) direction of the film F. The serial numbers in the X-axis direction of all the pixels are used as pixel addresses. The address may be periodic. Then, as shown in FIG. 8B, for example, a sub-address that is incremented by 1 for every 256 pixels is set on the X axis. Then, as shown in FIG. 8A, sub-address pixels are calculated in the X-axis direction.

  Then, the user refers to the film F on which the test pattern 30 recorded by the first test pattern recording process is recorded, and selects the correction parameter 32 of the division area 31 having the smoothest density by visual observation. Then, the correction parameter having the smoothest density selected and input by the user is received via the correction parameter input unit 4 (step S22).

  Then, the correction table calculation unit 5 calculates the correction amount of the sub-address based on the correction parameter input in step S22, and calculates the correction amount of the address (step S23). Here, with reference to FIG. 9, sub-address and address correction amount calculation will be described. FIG. 9 shows the relationship of the correction amount with respect to the X axis, (a) shows the correction amount corresponding to the correction parameter, (b) shows the correction amount corresponding to the subaddress, and (c) shows the correction corresponding to the address. Indicates the amount.

  For example, consider a case where +4 is input as the optimum correction parameter in step S22. First, as shown in FIG. 9A, points 41 and 42 are plotted from the correction amount of the correction parameter +4 in the graph of FIG. 5 and the X axis positions of the left region and the right region of FIG. A point 43 is plotted from the correction amount (= 0) of the correction parameter 0 of the X-axis position in the central region in the graph of FIG.

  Then, as shown in FIG. 9B, the correction amount at the subaddress calculated in step S21 is calculated and plotted so as to interpolate the point between the points 41, 42, and 43. Then, as shown in FIG. 9C, the correction amount at each pixel address is calculated and plotted so as to complement the correction amount point at the sub-address, and the shading correction table is completed.

  Here, with reference to FIG. 10, the speeding up of the calculation of the correction amount at the sub address will be described. FIG. 10 shows an example of the correspondence between addresses and subaddresses. As shown in FIG. 10, the address periodically repeats from 0 to 255 in decimal numbers along the main scanning direction. Similarly, the address is a hexadecimal number and periodically repeats from 0 to FF. Corresponding to the address, the subaddress is incremented from 0 to +1 in decimal notation for every 256 addresses. Similarly, the subaddress is incremented from 0 to +1 in hexadecimal.

  Here, consider the 5000th point in the total address. The decimal number 5000 is 1388 in hexadecimal. That is, the upper 2 digits of the hexadecimal number are 13 (19 in decimal number) and the lower 2 digits are 88 (136 in decimal number). Since the number of pixels corresponding to one of the sub-addresses (address number) is always 256 and constant, the upper 2 digits of the hexadecimal number of the address converted to decimal number corresponds to the decimal number of the sub-address, and the address 16 A value obtained by converting the lower two digits of the decimal number into a decimal number corresponds to the decimal number of the address.

If the Nth correction amount of the total address is expressed as E [N], the relationship between the address and the sub-address is used.
E [5000] = ((256-136) × E [19 (subaddress)] + 136 × E [20 (subaddress)]) / 256
As shown, linear interpolation is possible. That is, as shown in FIG. 9B, after calculating the sub-address correction value, the address correction amount can be calculated easily and at high speed, and memory saving can be easily achieved.

  Then, the shading correction table based on the correction amount calculated in step S23 is stored in the data storage unit 6 (step S24), and the shading correction table storage process is ended.

  After the end of the shading correction table storage process, the shading correction table stored in the data storage unit 6 is read when the medical image recording apparatus 1 outputs a medical image, and the image processing unit 11 uses the shading correction table. Thus, the image data input from the I / F 2 is subjected to shading correction, and the image output unit 10 records the shading corrected image data on the film F and outputs the image.

  As described above, according to the present embodiment, the user can easily select and input the optimal correction parameter by visually observing the test pattern, and the shading correction table is automatically created and stored based on the optimal correction parameter. A medical image can be shading corrected with high accuracy using an optimal shading correction table created by a user's simple operation input, and recorded on the film F.

  In addition, since a frame 33 for dividing the divided area 31 is recorded in the test pattern 30 on the film F, the user can easily select the correction parameter for the optimum divided area divided by the frame 33, and the correction accuracy of the shading correction can be improved. It can be improved further.

  Further, since the test pattern is divided into three divided areas in the main scanning direction, the user can select the optimum correction parameter more easily and with high accuracy with reference to the central area having the smallest correction amount.

  First, a shading correction table corresponding to the subaddress for each predetermined number of pixels in the main scanning direction is created, and the shading correction table corresponding to the address is created by interpolating the shading correction table corresponding to the subaddress. Therefore, the shading correction table can be created at high speed.

(Second Embodiment)
A second embodiment according to the present invention will be described with reference to FIGS. Since the apparatus configuration of the present embodiment is the same as that of the first embodiment, description thereof is omitted to avoid duplication.

  In the medical image recording apparatus 1, when a variation in light reflectance or surface tilt occurs on the mirror surface of the rotary polygon mirror 135 of the exposure unit 13, as shown in FIG. 22, as shown in FIG. Direction), the exposure amount corresponding to the variation in the light reflectance and the tilted surface is varied, causing streak unevenness in the X-axis direction in the Y-axis direction. This stripe unevenness is corrected for pitch unevenness.

  As shown in FIG. 11, a Y-axis address is defined. FIG. 11 shows the Y-axis address. There is a raster indicating the position corresponding to each scanning line on the film F, and since the rotary polygon mirror 135 has six surfaces corresponding to each scanning line, the Y-axis address ranges from 0 to 5 for each raster. Will appear periodically. That is, since stripe irregularities appear periodically, it is preferable to use a correction function in which the exposure correction amount is also periodic.

  FIG. 12 shows an example of a pitch unevenness correction table used for pitch unevenness correction. In the present embodiment, for example, as shown in FIG. 12, a sine wave as a function whose correction amount is periodic with respect to the Y axis is used as the pitch unevenness correction table.

  Next, the operation of the medical image recording apparatus 1 will be described with reference to FIGS. With reference to FIG. 13, a second test pattern recording process for recording a test pattern on the film F for selecting an optimal correction parameter for correcting pitch unevenness will be described. FIG. 13 shows the second test pattern recording process. For example, when a test pattern recording instruction is input via the correction parameter input unit 4, the second test pattern recording program stored in the ROM in the control unit 3 is read and triggered in the control unit 3. The second test pattern recording process is executed in cooperation with the CPU in the control unit 3 and the second test pattern recording program.

  First, a correction function is prepared based on a graph of the relationship between the phase correction parameter and the phase stored in the data storage unit 6, and a phase test pattern is created using each correction function (step S31). Now, with reference to FIGS. 14 and 15, the creation of the phase test pattern in step S31 will be described in detail. FIG. 14 shows an example of the phase relationship with respect to the phase correction parameter. FIG. 15 shows an output example of a test pattern for correcting pitch unevenness.

  In pitch unevenness correction for image unevenness in the sub-scanning direction, a test pattern composed of divided regions having a plurality of phase correction parameters is created. The observer observes the divided area of each phase correction parameter in the test pattern, and the observer selects the optimum phase correction parameter of the divided area with no image unevenness. This is because an optimal pitch unevenness correction table is generated using the selected optimal phase correction parameter.

  For example, the phase correction parameter when the phase (rad) is 0 as a reference (no phase shift) is created as shown in FIG. The phase correction parameter is a phase pattern corresponding to 15 points from −7 to 0 to +7. According to the relationship of FIG. 14, the phase increases as the phase correction parameter increases. When the phase correction parameter is 0, the phase is 0. When the phase correction parameter is positive, the phase is also positive. When the correction parameter is a negative value, the phase is also a negative value. That is, the image data is corrected so that the phase shift increases as the phase correction parameter is a positive value and increases. Further, when the phase correction parameter is 0, the phase shift is 0. Further, the image data is corrected so that the phase shift increases as the phase correction parameter becomes a negative value and becomes smaller.

  Then, as shown in FIG. 15, the test pattern 50 is divided into 15 parts as the number of phase correction parameters in the sub-scanning direction on the recording surface of the film F, and is divided into a central area, a right area, and a left area. In this way, 3 × 15 divided regions 51 are formed. The divided areas 51 are associated with the phase correction parameter from the highest value to the lowest value from the bottom to the top.

  In the divided area 51, the solid color image of one color density has a density corrected by a correction function corresponding to each phase correction parameter, resulting in a substantially uniform density image. Further, a phase correction parameter (value) 52 is placed in the divided area 51. Further, the divided area 51 is divided by a frame 53 as a mark indicating the density observation area. The observer can visually determine the divided area 51 having the smoothest density with no image unevenness in the sub-scanning direction with reference to the test pattern 50 recorded on the film F.

  The relationship between the phase correction parameter and the correction function will be described with reference to FIG. In the correction function corresponding to the phase correction parameter, the amplitude is fixed, and the phase to be corrected is changed. FIG. 16 shows a correction function for each phase correction parameter, (a) shows a correction function for phase correction parameter 0, (b) shows a correction function for phase correction parameter-1, and (c) shows a phase correction parameter. The correction function of -2. As shown in FIG. 16A, a phase correction parameter corresponding to a sine wave correction function in which the phase is 0 and the correction amount is 0 is set to 0. A point on the correction function indicates a raster of each scanning line in the sub-scanning direction.

  Then, as shown in FIG. 16B, the phase correction parameter of the correction function obtained by shifting the phase of the correction function of FIG. 16A to negative is set to −1, and as shown in FIG. The phase correction parameter of the correction function obtained by further shifting the phase of the correction function in (b) to be negative is set to −2. In this way, correction functions having phase correction parameters of −7 to 0 to +7 are prepared. The solid image is corrected using each correction function and is associated with each divided region 51 of the test pattern 50.

  Then, an amplitude test pattern is created based on the graph of the relationship between the amplitude correction parameter and the correction amount stored in the data storage unit 6 (step S32). Now, with reference to FIG. 17, the creation of the amplitude test pattern in step S32 will be described in detail. FIG. 17 shows an example of the relationship between the correction amount and the amplitude correction parameter.

  In pitch unevenness correction, a test pattern composed of divided regions having a plurality of amplitude correction parameters is created. The observer observes the divided area of each amplitude correction parameter in the test pattern, and the observer selects the optimum amplitude correction parameter of the divided area with no image unevenness. This is because an optimal pitch unevenness correction table is generated using the selected optimal amplitude correction parameter.

  For example, the amplitude correction parameter when the correction amount (%) is 0 as a reference (0) is created as shown in FIG. The amplitude correction parameter is an exposure amount correction parameter identification parameter corresponding to 15 points from -7 to 0 to +7. According to the relationship of FIG. 17, the correction amount increases as the amplitude correction parameter increases. When the amplitude correction parameter is 0, the correction amount is 0. When the amplitude correction parameter is a positive value, the correction amount is also a positive value. Thus, when the amplitude correction parameter is a negative value, the correction amount is also a negative value. That is, as the amplitude correction parameter is a positive value and increases, the image data is corrected so that the correction amount increases, and the output density increases. When the amplitude correction parameter is 0, the correction amount is 0. Further, as the amplitude correction parameter is a negative value and becomes smaller, the image data is corrected so that the correction amount is reduced, and the output density is lowered.

  Although not shown, like the test pattern 50 shown in FIG. 15, the test pattern 60 has a recording surface of the film F divided into 15 equal numbers as the number of amplitude correction parameters in the sub-scanning direction. Separated into left region. In this way, 3 × 15 divided regions 61 are formed. The divided areas 61 are associated in order from the highest value to the lowest value of the amplitude correction parameter from bottom to top.

  In the divided area 61, a solid image having a density of one color has a density corrected by a correction function corresponding to each amplitude correction parameter, resulting in a substantially uniform density image. Also, an amplitude correction parameter (value) 62 is placed in the divided area 61. Further, the divided area 61 is divided by a frame 63 as a mark indicating the density observation area. The observer can visually determine the divided region 61 having the smoothest density with no image unevenness in the sub-scanning direction with reference to the test pattern 60 stored in the film F.

  The relationship between the amplitude correction parameter and the correction function will be described with reference to FIG. The phase of the correction function corresponding to the amplitude correction parameter is fixed, and the amplitude to be corrected is changed. FIG. 18 shows a correction function for each amplitude correction parameter, (a) shows the correction function of the amplitude correction parameter 0, (b) shows the correction function of the amplitude correction parameter + 1, and (c) shows the amplitude correction parameter +2. The correction function is shown. As shown in FIG. 18A, the amplitude correction parameter corresponding to a sine wave correction function in which the Y-axis value is 0 and the correction amount is 0 is set to 0. A point on the correction function indicates a raster of each scanning line in the sub-scanning direction.

  Then, as shown in FIG. 18 (b), the amplitude correction parameter of the correction function obtained by increasing the amplitude of the correction function of FIG. 18 (a) is set to +1, and as shown in FIG. 18 (c), FIG. The amplitude correction parameter of the correction function obtained by further increasing the amplitude of the correction function is +2. In this way, correction functions having amplitude correction parameters of −7 to 0 to +7 are prepared. The solid image is corrected using each correction function and is associated with each divided region 61 of the test pattern 60.

  Then, the two test patterns of phase and amplitude created in steps S31 and S32 are input to the image processing unit 11 and recorded on the film F by the image output unit 10 (step S33), and the second test pattern recording process Is terminated.

  Next, a pitch unevenness correction table storage process for creating and storing a pitch unevenness correction table used for pitch unevenness correction will be described with reference to FIG. FIG. 19 shows pitch unevenness correction table storage processing. For example, the pitch unevenness correction table storage program stored in the ROM in the control unit 3 is read and triggered by the input of the pitch unevenness correction table creation instruction via the correction parameter input unit 4, and the RAM in the control unit 3. The pitch unevenness correction table storage process is executed in cooperation with the CPU in the control unit 3 and the pitch unevenness correction table storage program.

  First, the user refers to the film of the phase and amplitude test patterns 50 and 60 recorded by the second test pattern recording process, and visually corrects the correction parameters 52 and 62 of the divided regions 51 and 61 having the smoothest density. Select. Then, the smoothest density phase and amplitude correction parameters selected and input by the user are received via the correction parameter input unit 4 (step S41). The smoothest density phase and amplitude correction parameters may be input for each of the left region, the center region, and the right region. In this case, a pitch unevenness correction table is created for each of the left region, the center region, and the right region, and more accurate correction can be performed for each region.

  Then, the correction table calculation unit 5 selects and sets a correction function based on the phase and amplitude correction parameters input in step S41 (step S42). Then, the correction function set in step S42 is stored in the data storage unit 6 as a pitch unevenness correction table (step S43), and the pitch unevenness correction table storage process is ended.

  After completion of the pitch unevenness correction table storage process, the pitch unevenness correction table stored in the data storage unit 6 is read when the medical image is output in the medical image recording apparatus 1, and the image processing unit 11 uses the pitch unevenness correction table. Thus, the image data input from the I / F 2 is subjected to pitch unevenness correction, and the image output unit 10 records the image data subjected to the pitch unevenness correction on the film F and outputs the image.

  As described above, according to the present embodiment, the user can easily select and input the optimum correction parameter by visually observing the test patterns 50 and 60, and the optimum phase and amplitude correction function can be automatically selected based on the optimum correction parameter. The pitch unevenness correction table is automatically selected and automatically created and stored, so that the medical image can be corrected with high accuracy and recorded on the film F using the optimum pitch unevenness correction table by a simple operation input by the user. Can do.

  In addition, since the frames 53 and 63 for dividing the divided areas 51 and 61 are recorded in the test patterns 50 and 60 on the film F, the user can easily select the correction parameter for the optimum divided area divided by the frames 53 and 63. This can improve the correction accuracy of pitch unevenness correction.

(Modification)
A modification of the first and second embodiments will be described with reference to FIG. FIG. 20 shows the correction table storage process. In the first and second embodiments, the correction table for shading correction or pitch unevenness correction is created and stored. In this modification, a correction table for shading correction and pitch unevenness correction is created. And it is the structure to memorize. The device configuration of this modification is the same as that of the first embodiment.

  Next, the operation of the medical image recording apparatus 1 will be described with reference to FIG. With reference to FIG. 20, a correction table storing process for creating and storing a correction table used for shading correction and pitch unevenness correction will be described. It is assumed that the first test pattern recording process of the first embodiment and the second test pattern recording process of the second embodiment are executed in advance.

  For example, when a correction table creation instruction is input via the correction parameter input unit 4, a correction table storage program stored in the ROM in the control unit 3 is read and is appropriately stored in the RAM in the control unit 3. The correction table storage process is executed in cooperation with the CPU in the control unit 3 and the correction table storage program.

  First, as in step S21 of the shading correction table storage process, the correction table calculation unit 5 calculates an address in the main scanning direction and a sub address (step S51). Then, the user refers to the film F of the test pattern 30 recorded by the first test pattern recording process, and selects the correction parameter 32 of the division region 31 having the smoothest density by visual observation. Then, similarly to step S22 of the shading correction table storage process, the smoothest density correction parameter selected and input by the user is accepted as a shading correction parameter via the correction parameter input unit 4 (step S52). ).

  Then, the user refers to the film of the phase and amplitude test patterns 50 and 60 recorded by the second test pattern recording process, and visually corrects the correction parameters 52 and 62 of the divided regions 51 and 61 having the smoothest density. Select. As in step S41 of the pitch unevenness correction table storage process, the smoothest density phase and amplitude correction parameters selected and input by the user are input via the correction parameter input unit 4 as correction parameters for correcting pitch unevenness. Accepted (step S53).

  Then, as in step S42 of the pitch unevenness correction table storage process, the correction table calculation unit 5 selects and sets a correction function based on the phase and amplitude correction parameters input in step S53 (step S54). . Then, it is determined whether or not the correction table for all scanning lines has been completed (step S55).

  When the correction table for all the scanning lines has not been completed (step S55; NO), the correction parameter for the shading correction input in step S52 is input by the correction table calculation unit 5 as in step S23 of the shading correction table storage process. Based on the correction function input in step S54, the correction amount of the sub address of one unselected scanning line is calculated, and the correction amount of the address is calculated (step S56). Then, similarly to step S24 of the shading correction table storage process, a correction table for one scanning line based on the correction amount calculated in step S56 is stored in the data storage unit 6 (step S57), and the process proceeds to step S55.

  When the correction table for all scanning lines is completed (step S55; YES), the correction table for each scanning line stored in step S57 is collected and stored in the data storage unit 6 as a correction table for all scanning lines ( Step S58), the correction table storage process is terminated.

  As described above, according to the present modification, the user can easily select and input the optimum correction parameter by visually observing the test patterns 30, 50, and 60, and the optimum shading correction and pitch unevenness correction correction based on the optimum correction parameter. Since the table is automatically created and stored, the medical image can be recorded on the film F with high precision shading correction and pitch unevenness correction using an optimal correction table by a simple operation input by the user.

  In each of the above embodiments and modifications, the shading correction table and the pitch unevenness correction table stored in the data storage unit 6 are output to the image processing unit 11, and the image processing unit 11 uses the correction table. Although the image data is corrected by software, the present invention is not limited to this. For example, the shading correction table and the pitch unevenness correction table stored in the data storage unit 6 may be output to the exposure unit 13 and the correction table may be reflected in the emission intensity control signal of the laser beam in the modulation unit 131. In this case, the software calculation processing load is reduced without performing the correction processing calculation for all the pixels of the image data.

  In each of the above embodiments and modifications, the test patterns 30, 50, 60 are configured such that the divided regions 31, 51, 61 having substantially uniform density are separated by the frames 33, 53, 63 and recorded. However, it is not limited to this. As a mark for specifying the divided region, for example, a character, a mark, or the like can be used regardless of the shape.

  In each of the above-described embodiments and modifications, the photothermal silver salt medical image recording apparatus 1 that requires heat development using a laser is used. However, the present invention is not limited to this. For example, the present invention can be applied to a medical image recording apparatus such as a thermal head method. Further, as a medical image recording apparatus, a configuration using a silver salt recording type image recording apparatus requiring wet processing, a thermal recording apparatus using a heat mode laser, or an image recording apparatus for recording an image using a photosensitive thermal recording material. It is good.

  In each of the above embodiments and modifications, there is no limitation on the size of the recording size of a divided area as a substantially uniform density image, that is, a so-called “solid image”. Further, in each of the above embodiments and modifications, the divided areas of the test patterns 30, 50, 60 recorded on the film F are divided into the left area, the central area, and the right end portion in the main scanning direction. The number of divisions in the main scanning direction is not limited. The more the number of divisions in the main scanning direction, the more accurate correction can be made. However, since various processes become complicated, it is preferable to balance these. In the shading correction, it is preferable that the number of divisions in the main scanning direction is an odd number because the correction amount in the central region is the smallest and can be easily used as a reference for the correction amount.

  In the first embodiment, as shown in FIG. 9B, the shading correction table corresponding to the sub-address is created, but the present invention is not limited to this. For example, the configuration may be such that the process of creating the shading correction table corresponding to the subaddress is omitted, and the process proceeds from FIG. 9A to FIG. 9C.

  In the second embodiment, a pitch unevenness correction table is created and stored based on at least one of the amplitude correction parameter and the phase correction parameter, and corresponds to at least one of the amplitude and the phase. A configuration in which pitch unevenness correction is performed may be employed. Further, in each of the above embodiments and modifications, the correction table may be created and stored for each of at least one of the recording medium size and the recording pitch size.

  In addition, the detailed configuration and detailed operation of each component of the medical image recording apparatus 1 in each of the above embodiments and modifications can be appropriately changed without departing from the scope of the present invention. It is.

1 is a block diagram illustrating an internal configuration of a medical image recording apparatus 1 according to a first embodiment of the present invention. 2 is a diagram showing an internal configuration of an exposure unit 13. FIG. It is a figure which shows an example of a shading correction table. It is a flowchart which shows a 1st test pattern recording process. It is a figure which shows an example of the relationship of the corrected amount with respect to a correction parameter. It is a figure which shows the example of an output of the test pattern of shading correction. It is a flowchart which shows a shading correction table storage process. FIG. 4 is a diagram illustrating sub addresses of pixels to be recorded on a film F. (A) is a figure which shows the pixel for every subaddress recorded on the film F. FIG. (B) is a diagram showing the correspondence between pixel addresses and sub-addresses. It is a figure which shows the relationship of the corrected amount with respect to an X-axis. (A) is a figure which shows the correction amount corresponding to a correction parameter. (B) is a figure which shows the correction amount corresponding to a subaddress. (C) is a figure which shows the correction amount corresponding to an address. It is a figure which shows an example of the correspondence of an address and a subaddress. It is a figure which shows a Y-axis address. It is a figure which shows an example of a pitch nonuniformity correction table. It is a flowchart which shows a 2nd test pattern recording process. It is a figure which shows an example of the relationship of the phase with respect to a phase correction parameter. It is a figure which shows the example of an output of the test pattern of pitch nonuniformity correction. It is a figure which shows the correction function for every phase correction parameter. (A) is a figure which shows the correction function of the phase correction parameter 0. FIG. (B) is a figure which shows the correction function of the phase correction parameter-1. (C) is a figure which shows the correction function of the phase correction parameter-2. It is a figure which shows an example of the relationship of the corrected amount with respect to an amplitude correction parameter. It is a figure which shows the correction function for every amplitude correction parameter. (A) is a figure which shows the correction function of the amplitude correction parameter 0. FIG. (B) is a figure which shows the correction function of the amplitude correction parameter +1. (C) is a figure which shows the correction function of amplitude correction parameter +2. It is a flowchart which shows a pitch nonuniformity correction table storage process. It is a flowchart which shows a correction table storage process. It is a figure which shows the example of the nonuniformity of the exposure amount with respect to an X-axis. It is a figure which shows the example of the nonuniformity of the exposure amount with respect to a Y-axis.

Explanation of symbols

1 Medical Image Recording Device 2 I / F
3 Control unit 4 Correction parameter input unit 5 Correction table calculation unit 6 Data storage unit 7 Film transport unit 10 Image output unit 11 Image processing unit 12 D / A conversion unit 13 Exposure unit 131 Modulation unit 132 Laser light source unit 133 Condensing lens 134 Cylindrical lens 135 Rotating polygon mirror 136 fθ lens 137 Mirror 14 Thermal development unit 20 Modality L Laser light F Film

Claims (12)

In a medical image recording apparatus for recording a medical image on a recording medium,
Image recording means for recording the image by exposing and scanning the recording medium;
Test pattern recording control for causing the image recording unit to record an image on the recording medium as a test pattern with a solid image of a plurality of areas corrected by correction amounts based on a plurality of different shading correction parameters and an identification code representing the shading correction parameter Means,
Select a shading correction parameter that is determined based on the result of measuring the density in the main scanning direction of the solid image recorded by the test pattern recording control means and that minimizes the difference in the density of the solid image in the main scanning direction. Input means for inputting;
A shading correction table creating means for creating a shading correction table for correcting shading based on the shading correction parameter input by the input means;
Medical image recording control means for performing a shading correction on a medical image using the shading correction table created by the shading correction table creating means and causing the image recording means to record an image on a recording medium;
A medical image recording apparatus comprising:   The medical image recording apparatus according to claim 1, wherein the test pattern recording control unit causes the image recording unit to record a mark for indicating a region where the density is to be measured on the recording medium.   The medical image recording apparatus according to claim 1, wherein the number of solid images in the main scanning direction is an odd number.   The shading correction table creation means creates a temporary shading correction table corresponding to a subaddress indicating a position for each of a plurality of pixels in the main scanning direction based on the shading correction parameter, and sets a subaddress of the temporary shading correction table. 4. The medical image recording apparatus according to claim 1, wherein a shading correction table is created by interpolation. In a medical image recording apparatus for recording a medical image on a recording medium,
Different from the image recording means for exposing and scanning the recording medium to record an image, a solid image of a plurality of regions corrected by a correction amount based on a plurality of pitch unevenness correction parameters, and an identification code representing the pitch unevenness correction parameter as a test pattern Test pattern recording control means for causing the image recording means to record an image on the recording medium;
Input means for selecting and inputting a pitch unevenness correction parameter having the smallest pitch unevenness determined based on the result of visual evaluation of the solid image recorded by the test pattern recording control means;
Pitch unevenness correction table creating means for creating a pitch unevenness correction table for correcting pitch unevenness based on the pitch unevenness correction parameter input by the input means;
Medical image recording control means for performing pitch unevenness correction on a medical image using the pitch unevenness correction table created by the pitch unevenness correction table creating means, and causing the image recording means to record an image on a recording medium;
A medical image recording apparatus comprising:   6. The medical image recording apparatus according to claim 5, wherein the test pattern recording control unit causes the image recording unit to record a mark for indicating the region to be visually evaluated on the recording medium. In a medical image recording method for recording a medical image on a recording medium,
A step of recording an image on the recording medium as a test pattern with a solid image of a plurality of areas of the recording medium corrected by a correction amount based on a plurality of different shading correction parameters, and an identification code representing the shading correction parameter;
A step of selectively inputting a shading correction parameter that is determined based on the result of measuring the density in the main scanning direction of the solid image recorded in the image and that minimizes the difference in density of the solid image in the main scanning direction;
Creating a shading correction table for correcting shading based on the input shading correction parameters;
Performing a shading correction on a medical image using the created shading correction table and recording an image on a recording medium;
A medical image recording method comprising:   8. The medical image recording method according to claim 7, wherein in the step of recording the test pattern, a mark for indicating an area where the density is to be measured is recorded on the recording medium.   9. The medical image recording method according to claim 7, wherein the number of solid images in the main scanning direction is an odd number.   In the step of creating the shading correction table, a temporary shading correction table corresponding to a subaddress indicating the position of each of a plurality of pixels in the main scanning direction is created based on the shading correction parameter, and the subaddress of the temporary shading correction table The medical image recording method according to claim 7, wherein a shading correction table is created by interpolating. In a medical image recording method for recording a medical image on a recording medium,
A step of recording an image on the recording medium as a test pattern with a solid image of a plurality of regions corrected by a correction amount based on a plurality of different pitch unevenness correction parameters, and an identification code representing the pitch unevenness correction parameter;
A step of selectively inputting a pitch unevenness correction parameter having the smallest pitch unevenness determined based on a result of visual evaluation of the solid image recorded as described above;
Creating a pitch unevenness correction table for correcting pitch unevenness based on the input pitch unevenness correction parameters;
A step of performing pitch unevenness correction on a medical image using the created pitch unevenness correction table and recording an image on a recording medium;
A medical image recording method comprising:   12. The medical image recording method according to claim 11, wherein in the test pattern recording step, a mark for indicating the region to be visually evaluated is recorded on the recording medium.

Images